Linux is only marginally more difficult for users to learn than Windows XP, according to a study carried out by German usability testing agency Relevantive.

The tests, which compared SuSE Linux 8.2 Professional running the KDE 3.1.2 desktop environment to Windows XP, found that users were able to learn and complete tasks in Linux nearly as quickly as they could in Windows, and in some cases more quickly.

The tests may help to change the common perception of Linux as too technical for ordinary end-users, a key topic as the operating system makes its way onto desktop computers in governments and large businesses. The open-source operating system is considered one of the most dangerous competitors to Microsoft and its Windows desktop monopoly, not least by Microsoft chief executive Steve Ballmer.

The test subjects were not familiar with either Linux or Windows XP, although they may have used previous versions of Windows. Relevantive found that while most tasks took longer to perform on Linux, the difference was slight. "The use of the Linux desktop did not have considerable influence on the performance of the users," Relevantive said in the report.

The Linux testers were in fact able to complete some tasks more quickly than the Windows testers, including playing and burning a CD and using email. Relevantive found that in the case of CD burning, this was probably due to the fact that the function has been integrated into Windows Explorer, which went against the expectations of the Windows testers.

Linux generally made a good impression on users, with 87 percent saying it made usage "fun", compared with 90 percent for Windows XP. Eighty percent of the Linux testers said they thought they would be as competent with the new system as with their current operating system, compared with 85 percent for Windows XP. Most testers said they liked Linux better after having used it: 61 percent said the tests had improved their impression of Linux, compared with 55 percent for Windows XP.

Design, long considered a problem with Linux desktop software, made a relatively poor impression on the Linux testers, with 83 percent saying they were pleased with the design, compared to 100 percent of Windows XP users.

However, the tests turned up some oddities in Linux that affected usability. Users found the file system difficult to understand, despite the Konqueror file manager, Relevantive said, and the OpenOffice.org word processor was found difficult to use. Overall, the naming conventions used for desktop objects, menu items and the like confused many testers. They were unsure, for example, whether "directories" in Linux were the same as Windows' "folders".